Cash register



June 30, 1942. H. GELLER ETAL CASH REGISTER Filed Aug. 11, 1939 15 Sheets-Sheet l Hclmut Geller and Hans Driescher Inventors By M Their Attorney June-30,1942, H. GELLER ETAL CASH REG ISTER Filed Aug. 11, 1959 15 Sheets-Sheet 2 Helmut Geller nd H ns D escher Inventors y Their Attorney June 30, 1942. H. GELLER ET AL CASH REGISTER Filed Aug. 11, 1939 15 Sheets-Sheet S FIG. 4

Helmut Geller and Hans Driescher Inventors By M M Their Attorney June 30, 1942. H. GELLER ET AL 2,288,520

CASH REG IS TER Filed Aug. 11, 1939 15 Sheets-Sheet 5 Helmut Geller and Hans Driescher Inventors ByzML/w Their Attorney June 30, 1942. H. GELLER ETAL 2,288,520

CASH REGISTER Filed Aug. 11, 1939 15 Sheets-Sheet 6 FIG. 11A

Helmut Geller and Hans Driescher Inventors BYJKM/M Their Attorney June 30, 1942. H. GELLER ET AL cAsH REGISTER Filed Aug. 11, 1939 15 Sheets-Sheet 7 0 M 0 .w m 6 w I w fl 0 M9 m 8 IJ w )6 99 .TW k\ m.\ a a3 9 :EUW .L.---.----::

Helmut Geller and Hans Driescher Inventor: By M M Their Attorney June 30, 1942. H. GIQILLER ETAL 2,288,520

CASH REGISTER v Filed Aug. 11, 1939 15 Sheets-Sheet 8 F|G.12 V

00000000 a C, \o

Helmut Geller 5/ and Hans Driescher Inventors Their Attorney June 30, 1942. H. GELLER ETAL CASH REG IS TER 15 Sheets-Sheet 9 Filed Aug. 11, 1939 BYMM Their Attorney June 30, 19.42.

H. GELLER ETAL 045x REGISTER Filed Aug. 11. 1939 l5 Sheets-Sheet l0 FIG.18

Inventor.

I By

Their Attoniey June 30, 1942. H. GELLER ETAL 2,288,520

CASH REGISTER Filed Aug. 11, 1939 15 Sheets-Sheet ll Helmut Geller and Hans Driescher Inventor.

Their Attorney June 30, 1942. H. GELLER ETAL 2,288,520

CASH REGISTER Filed Aug. 11, 1939 15 Sheets-Sheet l2 FIG.2

Helrnut Geller and Hans Driescher Inventor! Their Attorney June 30, 1942- H. GELLER ET AL 2,288,520

CASH REGISTER Filed Aug. ll, 1939 15 Sheets-Sheet l3 Helmut Geller and Hans Driescher Inventors Their Attorney June 30, 1942. H. GELLER ET AL 2,288,520

CASH REGISTER Filed Aug. 11, 1959 15 Sheets-Sheetl4 Helmut Geller 3 and Hans Driescher Inventorl By M Their Attorney June 30, 1942. H. GELLER ET AL. 2,288,520

CASH REGISTER Filed Aug. 11, 1939 15 Sheets-Sheet 15 FIG.25 FIG.27

00.0 300 0a. ass 00.0

aw; 0a. 403 ll 4 6/ 38.3 402 00.0

Helmut Gall:- and Hans Driesclnfir Inventor-0 Their Attorney Patented June 39, 1942 ilbli'lED sm' Parent ()FFICE CASH REGISTER Application August 11, 1939, Serial No. 289,662 In Germany August 17, 1938 27 Claims.

This invention relates to improvements in cash registers and accounting machines of the general type illustrated in United States Letters Patent to Ernst Breitling Nos. 1,760,870, 2,052,444 and 2,064,147 granted respectively on June 3, 1930; August 25, 1936, and December 15, 1936.

It is generally the custom for public utility companies that supply communities with electric current, gas or water to furnish their numerous subscribers with a periodical statement of their accounts.

The consumption is first calculated from the previous and present readings of the meter and the amount of the bill to be presented to the consumer must then be obtained from this consumption by multiplying the units of consumption by the charge per unit. Such product must be obtained independently of the accounting machine, and is usually done by reading from multiplication product tables.

To avoid the resulting loss of time by such methods and the possibility of incorrect reading, it is an object of the present invention to provide means whereby the product is automatically selected and shown enlarged from reduced product tables provided in the machine according to factors calculated in the machine and/ or set up as desired.

It is therefore an object of this invention to provide in a machine having a balancing mechanism, means controlled thereby when the same is set to zero, for automatically indicating the balance or amount taken therefrom and for automatically selecting the product from a chart or table of products, the selected product being based on or controlled by said balance.

Another object of this invention is to provide a plurality of product tables based on various rates with means for selecting the table to be used and means for selecting an individual product from the selected table, the selection of said individual product being controlled by differential mechanisms controlled by the consumption of the commodity being used.

Fig. 1 is a perspective view of a portion of an entry machine with the cabinet or casing removed.

Fig. 2 is a plan view of the consumption indi cating apparatus.

Fig. 3 shows the electrical connections for the indicating apparatus for indicating the consumption calculated by the machine.

Fig. 4 is a front View of the consumption indicating apparatus.

Fig. 5 is a side elevation of the ratchet wheel connected with the reduced product table discs of Fig. 8, and the corresponding catch or stop device in the inoperative position.

Fig. 6 is a side elevation of the consumption indicating apparatus.

Fig. 7 shows a part of the ratchet wheel of Fig. 5 and the catch or stop device in the operative position.

Fig. 8 shows a product table for consumption values of 0-499 at a price of 0.075 cent per unit of consumption.

Fig. 9 is an elevation of the discs carrying the reduced product tables.

Fig. 10 is an elevation of two collector or commutator rings with the contacts sliding thereon and mounted thereon with the discs of Fig. 9.

Figs. 11A and 1113 together constitute a plan view of the complete arrangement for indicating a value from a product table.

Fig. 12 is a wiring diagram for indicating a value from a product table.

Fig. 13 is a section on line l3l3 of Fig. 15.

Fig. 14 is an elevation of the mirror reflecting a column of the product table.

Fig. 15 is an elevation of the mirror reflecting a line group from the selected column.

Fig. 16 shows the actuating means for the mirror of Fig. 15.

Figs. 17 is a section on line lll'l of Fig. 14.

Fig. 18 is an elevation of the shutter or screen and its setting mechanism for selecting a line.

Fig. 19 is a section through a modified form of a table selecting mechanism driven from the hundred position.

Fig. 20 is a cross section through said modified form of tabel selecting mechanism driven from the unit position.

Fig. 21 is a cross section through said modified form of the shutter adjusting mechanism driven from the decimal position.

Fig. 22 is a front elevation of said modified form of the table selecting mechanism driven from the hundred position.

Fig. 23 is a front elevation of said modified form of the table selecting mechanism driven from the unit position.

Fig. 24 is a plan View of said modified form of the table selecting mechanism.

Fig. 25 is an enlarged reproduction of the tables of said modified form, for the units 00, 10, 20, 30, 40, 50, 60, 70, 80, and 90, based upon the rate of .075 per unit.

Fig. 26 is a diagrammatic showing of the product indicating mechanism according to a second modification.

Fig. 27 is a diagram showing the connection for the projection apparatus of said second modification.

The entry machine comprises a number of rows of amount keys Bl (Fig, 1) and several rows of special keys 52 for adding mechanism' selection. By means of the amount keys the old and new state of the meter readings with the opposite indications are carried into the balance mechanism 63 in two consecutive operations of the machine. The consumption calculated in the balancing mechanism 63 is printed in the following machine operation by setting the balancing mechanism to zero. In order that all the amounts necessary to the preparation of a customers bill may be obtained simultaneously during this operation, the product table upon which certain of these amounts are based is selected, before the operation is begun, under control of special keys M according to the tarifi or charge per unit. These special keys 64 comprise a complete units row of nine digit keys and a tens row containing four keys. It is thus possible to select forty nine different product tables by means of the special keys 84.

Consumption indicating apparatus By setting the balance mechanism (Fig. l) to zero, differential member 65, connected with the racks 56 which in turn are connected with the type wheels of the printing mechanism are set in a known manner (see last two Breitling patents cited above). In the construction shown, an arrangement is also provided to make the printed consumption visible also by means of a special indicating device. Inasmuch as it is assumed that the monthly consumption does not as a rule exceed a three position value, only the three lowest racks 66 are connected with the indicating mechanism. At the end of each rack 68 of the three lowest values there are contact springs 81 and 68, each contact spring 6! being adapt-ed to slide over a series of fixed contacts 69 and each spring 63 adapted to slide over a series of fixed contacts 10. The three rows of fixed contacts 69 (Fig. 3) are each connected by leads H formed into a cable with a set of incandescent lamps 12, so that after finally setting the three lowest value racks B6, lamps 12 can be illuminated corresponding to this setting. Current is passed from the positive line connection 85 of the source of supply, through the contact spring 92 and fixed contact 9| (spring 92 being moved into contact with the fixed contact 9! by the rack 98 when taking an amount from the balancing mechanism, as later stated), over a conductor B1, through the contact springs 6'! which are connected by means of insulating members 13 with racks 66 through the leads H, lamps 12 to the point 88 of the negative side.

It would be possible to carry a plate with the corresponding figure and adapted to be illuminated translucently, in front of each lamp '12. This, however, would have the disadvantage that the figures of a three-figure number indicated in this manner would not appear in a row. Therefore, in order to make possible the indication of three-figure numbers in a horizontal row by means of the three rows of incandescent lamps 12, each row of lamps I2 is positioned in a curved support 14 (Fig. 6). The curvature of support 14 corresponds to an are which is constructed about the centre of the indicating point 16 of a ground glass disc viewing screen 15. But, also viewed in a horizontal plane, the three lamp supports are disposed along an arc (Fig. 2) which is constructed about the central line of a diapositive H. The sole purpose of this arcuate arrangement of the three lamp upports 14 is to indicate three difierent figures of a three-figure number by means of the diapositive ll (Fig. 4) having onlya single vertical number row. As clearly shown on Fig. 2 the rays passing from the lamps of the three rows meet in the diapositive TI, to again separate and be distributed over the complete width of the indicating point 16 of the ground glass disc or viewing screen 15. The diapositive ii is located at the narrowest point of a funnel 18 which is attached by means of screws 79 to the incandescent lamp supports 14.

Inasmuch as th three lowest value racks '66 are also set in entering the old and new state of the meter at numerical value, this value would also be indicated similarly on the disc '95 if current were passed continuously to the contact springs 6'! (Figs. 1 and 3). However, the indication of the three lowest orders or values of the old and new state of the meter is of no importance; and therefore the arrangement i such that only when the consumption is printed, that is, during the operation through which the balancing mechanism is set to zero, are contact springs 61 connected with the current source. For this, use is made of a rack 96 which is set by the differential member 65 of a predetermined special differential mechanism, the function of which is to select an accumulative adding mechanism for the reception of the amount from the balancing mechanism. Inasmuch as the adding mechanisms for the reception of such amounts assume the two outermost positions in their series, the rack set by this special differential mechanism comes into a predetermined setting range only when taking an amount from the balancing mechanism. Provided in this range is a fixed contact 9| with which a contact spring 92 connected by means of insulating members 89 (Figs. 1 and 3) with rack 9E1 can come in contact. The circuit to the contact springs 6! is closed only when such movement takes place. This circuit, as above explained, as from point 86 (Fig. 3) on one side of the source of supply, through the spring 92, fixed contact 91 (at this time contacted by 92) over conductor 87, through the spring 67, selected contacts 59, associated leads H, and lamps 12, to the point 88 of the other side of the source of supply. As a result, indication by means of the lamps 72 can take place only during the machine operation serving to set the balancing mechanism to zero.

Selection of the product tables As stated, the product tab-1e which contains all the products formed with the corresponding price per consumption unit is selected under control of the special keys 8 3 as the sum to be billed to the consumer. Fig. 8 shows such table for unit price of .075 cent, in which all products are put in round numbers at whole cents. Inasmuch as a three-figure number is provided for, the consumption the table must actually show a thousand different values, that is, the products of all numbers in the range of 0 to 999 with the factor 0.075. In the exemplary embodiment shown, however, it is assumed that, as a rule, a monthly consumption of 499 units is rarely exceeded, so that the product tables need contain only 500 values.

The diapositives 93 (Fig. 9) containing these cylinder I9 I.

tables suitably reduced are attached to the periphery of a rotatable disc 94 secured to a shaft 96, and can be carried into the range of a projection apparatus 95. In order to select a predetermined product table; that is, to hold a predetermined diapositive 93 in the range of the projector 95, a ratchet wheel 91 (Figs. 5, '1 and 11B) is also attached on the shaft 99 carrying the disc 94. A stop 99 can be carried into the range of the ratchet teeth 98 of wheel 91. For this purpose the stop 99 is attached rotatably at the end of a piston rod I99, which slides in a brake Associated with the stop 99 is a magnet I92 which upon being energized rocks the stop 99 counter-clockwise about its pivot pin, until pins I93 (see also Fig. 113) extending from both sides thereof contact the lower horizontal edges of two fixed plates I94. In this manner the upwardly extending extension of the stop 99 passes into the range of the ratchet teeth 98 (Fig. '1).

.In order to hold the desired diapositive 93 in the range of the projector 95 the magnet I92 must be energized according to the depressed special key or keys 54. A rack I95 (Fig. 1) is set from the unit key row 94, and a contact spring I91 attached to said rack by means of an insulating member H9 is adapted to slide over a series of fixed contacts I98. A contact spring I69, which co-operates with a series of fixed contacts H9, is also attached by means of an insulating member l2i to a rack I99 set by the tens row 64. The five fixed contacts H9 are connected by the leads I i I (Fig. 12) forming a cable I12, with the five annular members of a collector ring H3. Likewise, each fixed contact I98 is connected by one of the leads I'I4, combined to a cable H5, with each group of five of the fifty plates of a second collector ring H6, whereby each two of the plates connected with the same contact I98 are removed ten plates from each other. Ten plates of the outer collector ring H6 correspond to each annular member of the inner ring H3.- The two collector rings H3 and III; are mounted on a med plate II1 (Figs. 10 and 11B) concentric with the shaft 96, on which latter, in addition to the disc 94 carrying the diapositives 93, and the ratchet wheel 91, there is also attached an arm I'I8 which carries two conductively interconnected brushes H9 which, however, are insulated from arm H9. On rotation of arm H8 the one brush slides on the platesforming the inner ring H3 and the other on the plates forming the outer ring H6. When the brushes simultaneously engage plates which are connected through the fixed contacts I98 and H9 with the contact springs I91 and I99, a circuit is closed which is utilized to energize the magnet I 92 and thereby hold ratchet wheel 91 and disc 94.

It is, of course, obvious that the disc 94 is to be thus held only during the machine operation for taking the sum from the balancing mechaniism. Therefore, there is a second contact spring 439 (Figs. 1 and 12) on rack 99 which comes in contact with a fixed contact I3I on extracting sums from the balancing mechanism. Since the plus (-1-) pole of the current source is connected with the contact spring I39, on its contact with the fixed contact I3I the circuit is passed further over a conductor I32, a condenser I33 and the winding I of a relay I34 to the minus pole of the current source. If the winding I35 is set under current by the establishment of this circuit the switch I38 of relay I34 is closed. The following circuit is thereby formed: From the plus pole of the current source through a choke I31, a condenser I38, to the negative side of the line. The circuit also is from the choke I31, through the switch I39 of the relay I34, a conductor I39, the winding of the magnet I92, a conductor I49, the contact spring I99, one of the fixed contacts N9, the corresponding conductor III and the corresponding plate of the collector ring H3, the two brushes H9 of arm H9, the plates of the outer ring lying in the range of the annular members of ring H3 connected with contact spring I99, which plates of said outer ring IIB are connected over a conductor H4 and a fixed contact I98 with the contact spring I91, then further over a conductor I4I, a switch I42 and two conductors I43 and I44 to the minus pole of the current source. The switch I42 is open as long as a switch I45 for the motor circuit of the machine is closed. Switch I42 is closed only when switch I45 is opened, which indicates the completion of the entry operation of the machine. The circuit for the winding of magnet I92 can thus not become active before this.

Switch 142 is provided to permit the activity of the circuit for the winding of magnet i92 only when the final adjustment or differential setting of the racks I and I99 is attained.

If the described circuit is established and current passes through the winding of magnet '92, stop 99 is raised and its upwardly directed extension carried into the range of the teeth 99 of ratchet wheel 91. In order to produce shockfree stopping of wheel 91 the tooth 98 first contacting with the upward extension of stop 99 (Fig. 5) moves the latter together with the piston I99 to the left, whereby the cylinder effects a smooth braking, until a second upward extension 14% (Fig. '7) is applied against bent down flaps of a fixed block I41. When this passes into the position shown on Fig. '1 the corresponding diapositive 93 is exactly in the ray or beam path of the projector 95. During the interval from the raising of the stop 99 until it is moved into the left end position determined by the block I41 the outer brush I I9 has again left the conductive plate of ring H5 through which the circuit to the magnet I92 had been made, thereby de-energizing said magnet I92. This, however, does not change the active position of stop 99, as the latter is held in raised position by friction with the active ratchet tooth 98.

The rotation of the shaft 96 with the disc 94 and wheel 91 attached thereto is effected by a continuously rotating motor I48 (Figs. 11B and 12) which can be arrested by means of the ratchet wheel 91. In order to prevent shocks from reaching the motor I43 a spiral spring I49 (Fig. 11B) is interposed between a shaft I69, driven by motor I48 and the shaft 99. If the contact spring I39 (Fig. 12) is removed from the fixed contact I3I, during the machine operation following the printing of the consumption, it comes in contact with a fixed contact IBI, so that a circuit is closed from the plus side, over a conductor I62, a condenser I 53 and the winding I64 of a relay I65 and conductor I96 to the negative side. The winding I64, through which current passes, shifts the two switches I61 of the relay I65 and thereby reverses the rotational direction of the motor I49, so that the shaft 95 with the ratchet wheel 91 (Figs. 5 and 7) de scribes a counter-clockwise movement. The active ratchet tooth 98 is thereby removed from the upward extension of stop 99, whereby the latter resumes its normal position through the action of its spring I68. The interposed condenser I63 prevents current from fiowing continuously through the winding of the relay I65. When the condenser I63 is charged a state of equilibrium is established, and current ceases to fiow through the winding I64, whereby both switches I67 resume their normal positions; and the motor I68 is again shifted to normal rotation. The shaft 96 then rotates until the stop 99 is again carried into the range of the teeth 98 of ratchet wheel 97.

Selection of a predetermined product from the selected table Assuming that a consumption of 367 units has been computed by the balancing mechanism, a value of $27.53 will be given by the eighth column from the left and the thirty-seventh line from the top of the table according to Fig. 8. It must thereby be kept in mind that said table is so greatly reduced in dimensions that its height is about .59 inch and its width .39 inch on a diapositive 93.

In order to obtain the indicated value of $27.53, it is first necessary to get the eighth column from the left from the table of Fig. 8. For this purpose use is made of a mirror I69 (Figs. 11A, and 1.4 to 17) which is connected with an armature I76 secured to a shaft I7I. The mirror I69 is carried by a plate I56 having a short trunnion II and a long trunnion I52 to mount the plate I56 and mirror I69 in a bracket I53. Secured to the long trunnion is a worm wheel I54 driven by a worm pinion I55 secured to a shaft I56 mounted in a frame I57. Also secured to the shaft IE6 is a knurled collar I56 driven by a knurled segment arm I59 fastened to the shaft I7 I. Thus, the mirror I69 is driven by the armature I79 when the magnet I72 is energized as will be later described. The armature I79 rotates between arms of a magnet I72, which is energized by means of a winding I73. The magnet I72 tends to impart a counter-clockwise movement to the armature H9 which is inclined with respect to the magnet arms. The magnitude of the rotation to be imparted to armature I76 and therewith mirror I69 is determined by a segment I74 attached to the shaft I'7I, said segment I74 having nine bent fingers I75. Fingers I76 of stop springs I77 are normally outside of the path of the fingers I75 of the segment I74. Co-ordinated with each spring I77 is a magnet I78 which when energized attracts the corresponding spring I77 and carries its finger I76 into the path of the corresponding finger I75. If current passes through the winding I79 and no magnet I78 is energized, the mirror I69, armature I76 and segment I74 can describe their complete counter-clockwise movement, which is determined by the tenth finger I79 contacting fixed stop I69. The finger I79 is normally applied against a stop IBI, and thereby determines the inoperative position of the mirror I69, armature I76 and segment I74.

As shown by the circuit diagram of Fig. 12, the winding I73 lies in a circuit passing from the positive current source over a conductor I96, the winding I73, a second conductor I9I and a switch I92, to the conductor I64 which leads to the negative pole. The switch I92, like the switch I42, is closed only when the motor switch for the entry machine proper is opened.

The windings of the magnets I78 are all con-- nected with a conductor I93, which is connected with the positive pole of the current source. The other winding ends of the magnets I78 are connected, by conductors I94 combined into a cable I95, with the contacts 76 co-ordinated with the lowest value racks 69. Thus, a circuit can be closed from the positive pole of the current source over the conductor I93, that winding of a magnet I79 which is connected by one of the conductors I94 and the corresponding fixed contact 76 with the contact spring 68, conductor I4I, switch I42 and the conductors I43 and I44 to the negative pole of the current source. The energization of a magnet I78 produced by such cir-' cuit causes the attraction of the corresponding stop spring I77, which therewith determines the movement of the mirror I69. The latter, on rotation, comes into a position such as to reflect from the diapositive 93 only a certain predetermined column of the product table (Fig. 8) sharply on a second mirror I96 (Figs. 12 and 15) which can rotate in a plane perpendicular to the rotational plane of the mirror I69. The mirror I96, like the mirror I69, is connected with an armature I97 which is rotatably mounted between the arms of a magnet I98. The Winding I99 of this magnet is connected in parallel with the winding I73 by conductor 266 and 26I.

A segment 262 (Figs. 13 and 15), provided with four bent fingers 263, is connected with the armature I97, the segment 262 and armature I97 being secured to a shaft 264. There is provided a number of stop members 265 formed as armatures of electro magnets 266 and each normally outside of the path of the fingers 263. On energization of a magnet 266 by means of its winding 267, through which current passes, the corresponding member 265 is carried into the path of the corresponding finger 263. One end of each of the windings 267 is connected by a conductor 268 (Fig. 12) to the positive pole of the current source, while the other ends of windings 267 are connected by conductors 269 combined to a cable 2I6 with the four lowest value contacts 76 co-ordinated with the third rack 66 from the right. A circuit is thus established from the plus pole of the current source over the conductor 268, that winding 267 whose cor-' responding conductor 269 is connected through the corresponding fixed contact 76 with the contact spring 68 of the third rack 66, also over the conductor I 4|, the switch I 42 and conductors I43 and I94 to the negative pole of the current source. The function of the mirror I96 is to reflect, by the aid of a fixed mirror I89 (Fig. 11A) a group of ten consecutive lines from the column reflected by the mirror I69 from the product table, against a screen or shutter 2, having therein a plot or window 2I8, hereinafter described in more detail, which allows a portion of the reflected group of lines to pass through the screen in the direction of the ground glass disc 75 (Figs. 11A and 11B). Since the product table of Fig. 8 has fifty lines in all, the line group mirror I96 must be capable of assuming five different positions. Four positions are determined by the four magnets 266, while the fifth is determined by a fixed stop 2I2 (Fig. 15) which limits the maximum travel of the segment 262. The latter can describe its maximum travel when the contact spring 68 of the third rack 66 passes to the fixed contact 76 corresponding to the figure 5 in this value position. This contact 76 is not connected with a winding 267 and therefore can not carry a contact member 205 into the path of a finger 203. The five fixed contacts corresponding to the values 5-9 of the third contact row I are connected with a conductor 2I3 (Fig. 12) passing to a signal lamp 2I4, said conductor 2E3 being connected through a conductor 2I5 with the positive pole of a current source 2I6. The ne ative pole of this current source is connected by a conductor 2|I with the contact spring 68 of the third rack 66'. Thus, if the third rack 66 is set to a value exceeding the value 4 the signal lamp 2I4 lights, which shows that a value can not be taken for such consumption from a product table. This arrangement may be omitted if the product table according to Fig. 8 contains 1000 instead of 500 values.

The function of the screen or shutter 2II (Figs. 11A, 11B, 12 and 18) is to permit only a single one of the ten values reflected by the mirrors I96 and I89 to pass through its narrow slot or window 2I8 to the disc 75. The screen 2 is carried by a rod 230 attached on a shaft 23I of a small electric motor 232. The circuit for the motor 232 is from the plus line over conductor 233 then over conductor 234 and over a Switch 235 and conductor 236 to the minus conductor I44. The switch 235 is so connected with the stop 99 for the ratchet wheel 91 that said switch 235 is closed when the stop 99 is raised. By means of the motor 232 the rod 230 and the shutter 2H are moved counterclockwise out of the inoperative position shown in Fig. 18. A contact are 231 provided with bent over lugs 238 (Fig. 18) is connected with the screen ZII. Stops 239, with each of which an electromagnet 240 is co-ordinated, can be carried into the path of the lugs 238 (see also Fig. 11A). The windings 24I of the magnets 240 are connected, by conductors 242 combined to form a cable 243, with the fixed contacts I0 co-ordinated with the second rack 66 from the right (Fig. 1). The other ends of all the windings 24I are connected to a conductor 244 which is connected through a switch 245 of the relay I65, and a conductor 246 with the positive pole of the current source. When the switch 245 is closed a circuit passes from the positive pole of the current source over conductor 246, switch 245, conductor 244, that winding 24I in contact with the spring 68 of the second rack 66 M turned according to the adjustment of the corresponding racks 33 Thi positioning or adjustment of the mirrors I59 and I96 is, however, of no significance in connection with machine operations in which the consumption is not printed, as the ratchet wheel 97 is not stopped,

but the disc 94 (Fig. 9) is in continuous rotation. This does not apply to the screen or shutter 2, as the motor 232 is under current only when the ratchet wheel 91 is stopped. The energization of a magnet 240 according to the adjustment of the corresponding rack has no effect on the shutter 2H when the latter is in its inoperative position.

In connection with the machine operation following the indcation of the consumption, how- I'- ever, the stop 99 must first be released by backward rotation of the wheel 91. Thus, the motor 232 can also run for this time, since the circuit for this motor 232 is held closed by the switch 235 until the stop 99 is released from the ratchet wheel 91. In order that thereby the screen 2II will not be held by a stop 239 energization of a magnet 240 is prevented in the following manner:

As stated, during the machine operation following the indication of the consumption, the contact spring I30 (Figs. 1 and 12) passes from the fixed contact I3I over to the fixed contact IEI, so that current passes for a time over the conductor H32, over the condenser I53 and through the winding I64 of the relay I65. The energization of the relay I results not only in a periodical reversal of the rotational direction of the drive motor I48 for the shaft I60, but also in the opening of the switch 245, whereby the current to the windings 24! i cut ofi. The shutter 2H can thus be carried by the motor 232 into a position determined by a stop 2 51 (Figs. 11A, 12 and 17) before the switch 245 is again closed, after the current ceases to pass through the winding Hi4, and the magnet 240 corresponding to the position of the corresponding rack 66 can be supplied with current, and in which position of the screen 2H the ground glass disc I5 is completely darkened. In the initial or starting position, the rod 230 of screen 2II is applied against a fixed stop 248, being returned to such position when the magnets 24I are de-energized, whereby the disc F5 is also darkened.

Modified form The selection of the involved product from the product tables provided on reduced scale in the machine can also be effected in purely mechanical manner, according to an exemplary construction described herewith with reference to Figs 19 to 24.

The entry operation is the same, that is, the old and the new state of the meter together with the opposite notations are entered in the balancing mechanism in two consecutive machine operations and the thereby calculated consumption is printed in a third operation by setting the balance mechanism to zero.

In this case it is also assumed that the consumption between two meter readings does not exceed 499 units; and hence when the balancing mechanism is set to zero only the amount differential mechanisms of the three lowest positions (units, tens, hundreds) are actuated, whereby they set the three corresponding differential members, 296, 25I and 202 (Figs. 20, 21 and 19 respectively) to the value.

The units differential member 260 (Fig. 20) is connected through gears 264 and 295 with a gear 265 journalled on a shaft 29'! (Fig. 23). The tens differential member 25I (Fig. 21) is connected through gears 268 and 299 with a gear 2% journalled on said shaft 231 and the hundreds differential member 262 (Fig. 19) is connected through intermediate gears 2'sl and 212 with a gear 213 journalled on the shaft 261.

The gear 213 of the hundred position (Figs. 19, 22 and 24) is connected through a train of gears 2'54, 215, 216, 21?, 2'58 and 279 with a disc journalled on a fixed shaft ZBI in such manner that on a movement of the corresponding differential member 232 of one advance step, the disc 230 is given a fifth of a rotation counterclockwise (Fig. 22). Five pins 282 are attached 

